Logitech left solar-powered keyboards in the dark for over a decade, but it’s launching a new one today. Just like the K760 before it, its new $99.99 Signature Slim Solar Plus K980 can only be powered with light. There’s no USB port or swappable batteries. Instead, it features a cell that can convert solar or artificial light — 200 lux at minimum — into power to charge its battery, which the company says will last for up to 10 years. Once fully charged, the company says the K980 can…